Cooling system



G. E. HULSE COOLING SYSTEM Nov. 14, 1939.

Filed Nov. 27, 1936 5 Sheets-Sheet 1 INVENTOR (jean e E. Ha [so 614% GJVMZQ ATTORNEYS G. E. HULSE COOLING SYSTEM Nov. 14, 1939.

Filed Nov. 27, 1936 3 Sheets-Sheet 2 G. E. HULSE COOLING SYSTEM Nov. 14, 1939.

Filed Nov. 27, 1936 5 Sheets-Sheet 5 INVENTOR George E. Hulse ATTORNEYS Patented Nov. 14, 1939 UNITED STATES/ COOLING srsrau George E. Hnlse, New Haven, Conn; assignor to The Safety Car Heating d; Lighting Company. a corporation of New Jersey Application November 27, 1936, Serial No. 112,939

' 19 Claims.

This invention relates to a cooling system particularly designed for use on railroad cars or the like.

One of the objects of this invention is to provide a cooling system efficient and practical in operation. Another object is to provide a system of the above character characterized by simplicity of design, reduction in number of working parts and reliability in operation. Another object is to provide a system of the above character which will utilize water as the refrigerating medium and which will operate efliciently for substantial periods of time with a comparatively small supply of water. Another object is to provide a system of the above character which will operate efficiently under a variety of weather conditions and which may be subjected to low temperatures without damage to any of its parts. Another object is to provide a system of the above character wherein a substantial portion of the water in certain of the delicate parts thereof may be drained when the apparatus is subjected to low temperatures. Another object is to provide a system of the above character wherein a suflicient quantity of water may be drained from certain of the parts to avoid damage thereof while maintaining sufficient water in the system to keep it in readiness for operation upon comparatively short notice. Other objects will be in part obvious and in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts as will be exemplified in the structure to be hereinafter described and the scope of the application of which will be indicated in the following claims.

in the accompanying drawings in which is shown one of the various possible embodiments oi my invention,

Figure l is a partially diagrammatic top plan view of a large portion of the apparatus used in my cooling system and as installed on a railroad car or the like;

Figure 2 is a partially diagrammatic longitudinal vertical sectional view of the apparatus shown in Figure l and taken along the line 2-2 in Figure 1;

Figure 3 is a partially diagrammatic transverse vertical sectional view cf the apparatus shown in Figure l and taken along the line 3-3 in Figure 2;

Figure 4 is a diagrammatic view of a preferred control circuit for my system.

Similar reference characters refer t0 811M131 parts throughout the several views of the draw- For a better understanding of certain of the important features of this invention, it might here be pointed out that considerable difficulty 6 has been experienced in developing cooling" systems for railroad career the like which will operate efficiently and remain undamaged when subjected to a variety of weather and more particularly temperature conditions. This is par- 10 ticularly true in systems utilizing water as the refrigerant because of the comparatively high freezing point of water and the necessity for subjecting such systems to freezing temperatures for long periods of time. Various expedients for 15 protecting such systems have been tried in the past b'ut'have invariably been the cause of considerable difflculty and inconvenience. This is an important factor in railroad car conditioning where, for example, a car may leave New York 20 in freezing temperatures and arrive inFlorida a day later wheie air conditioning is required. Under such circumstances it is usually necessary to employ apparatus which, while adequately protected against freezing temperatures, may 25 start the cooling operation on short notice. It has been suggested that the various parts of the cooling apparatuscontaining water could be covered by a heavy layer of insulating material. Such insulation, however, is expensive and is obviously inconvenient due to the inaccessability of many of the working parts which increases repair difficulties. One of the objects of this invention is to provide a cooling system in which the above-mentioned difliculties as well as many others are successfully overcome.

' Referring now to Figure 1 of the drawings, there is shown a supporting frame generally indicated at It which may take any suitable shape but which preferably comprises a pair of lcngi- 40 tudinal beams II and I2 and a pair of transverse beams and H. Bridging longitudinal beams II and II are spaced supporting elements II, l8, l1 and I8. Frame l0 and more particularly supporting elements l5, I6, I 1 and II have suspended therefrom a portion of my cooling apparatus comprising an electric motor IS, a rotary pump 20, a sump tank 2|, a rotary pump 22 and an electric motor 23. Frame It! with its associated parts to be presently described is preferably mounted in any suitable manner beneath a railroad car.

Thus, motor I! is suspended from and suitably secured to supporting elements It and I6 by bolts 24 or the like. A driving shaft 25 of motor I9 is connected to the driven element of rotary pump 28 and the intake side 28 of pump 28 is connected to sump tank 2|. As best shown in Figure 2, a pair of bracket members 21 and 28 are connected to longitudinal beams H and I2 and extend about sump tank 2| to hold the tank in position under the frame.

Motor 23 is suspended from supporting elements l1 and I8 and preferably secured thereto by bolts 29; the driving shaft 38 of motor 23 is connected to the driven element of pump 22. Accordingly, pump 22 and motor 23 are suspended beneath the frame |8 as is more clearly shown in Figure 2. v

As best shown in Figures 1 and 3, a box-like casing 3| is located above frame l8 and contains other parts of the cooling apparatus. Casing 3| is desirably located above motors i9 and 23, pumps 28 and 22 and sump tank 2| and their connecting parts (Figure 3), all as will be more fully pointed out hereinafter.

As diagrammatically indicated in Figure 1, casing 3| contains a condenser tank 32, an evaporator 33 and a steam ejector 34. Ejector 34 is connected to a steam line 83, preferably the regular steam line of a railroad car, controlled by a motor actuated valve 84. Included within tank 32 are condenser coils 18 diagrammatically indicated in Figure 1 as connected to the outlet side of ejector 34 by a pipe 18, and a spray device 11 for cooling the coils. Spray device 11 is connected to a fitting 35 and fitting 35 is connected to a Venturi-purge 38 by pipes 31 and 38, all as best shown in Figure 1. Purge 38 is connected to a fitting 39 and fitting 39 is connected to the outlet side 28a of pump 28 by a pipe 48. A fitting 4| is connected to the bottom of condenser tank 32 and a pipe 42 is connected to fitting 4|. Pipe 42 extends downwardly as best shown in Figure 3 and is connected to a fitting 43 forming the inlet for sump tank 2|. Evaporator 33 includes a spray head 89 (Figure 1) connected to a pipe 81 as will be more fully explained hereinafter.

As best shown in Figure 2, an electrically operable valve 44 constructed to open when energized is connected through a pipe 8| to a make-up water tank 88 which has its top connected through a vent pipe 288 to sump tank 2|. Makeup tank 88 is elevated and is provided with no air inlet except vent pipe 288. Thus, water fiows from tank 88 only when the water level in tank 2| is below the end of pipe 288. Valve 44 is connected to an inlet pipe 45 which is in turn connected to a strainer 48. Strainer 48 is connected to a T-fitting 41 by a pipe 48. Referring to Figure 1, one outlet 41a of fitting 41 is connected to a strainer 49 by a pipe 58; the other side of strainer 49 is connected to the gland of pump 22 by a pipe 5|.

Referring back to Figure 2, outlet 41b of fitting 41 is connected to a fitting 52 by a pipe I58. Outlet 52a of fitting 52 is connected to a fitting 53 leading into sump tank 2| (Figure 2) by a pipe 54. Outlet 52b of fitting 52 is connected to a thermo-' static valve 55 by a pipe 58.

Thermostatic valve 55 has a drain outlet |5| and the valve is constructed to open and remain open at or below a certain temperature. A convenient opening temperature for valve 55 has been found to be F. As best shown in Figure 2, the line comprising pipe 45, strainer 48, fitting 41, pipe I58, fitting 52, pipe 58 and thermostatic valve 55 slants downwardly toward the left-hand side of the figure or toward valve 55. Cons quently.

upon the opening of valve 55 all water in this line and its connected parts will drain out through the valve. Fitting 53, which is connected to valve 55 by way of pipe 54, fitting 52 and pipe 58, enters sump tank 2| substantially above the bottom thereof and desirably along the horizontal center line of pump 28 and its connected parts, as more clearly shown in Figure 2. Consequently, the opening of thermostatic valve 55 drains sump tank 2|, pump 28 to the level of fitting 53 and, of course, condenser tank 32 located thereabove in casing 3| (Figure 3).

A pipe 51, diagrammatically indicated in Figures 1 and 3, is connected to the bottom of evaporator 33 and connected to a fitting 58. Fitting 58 is connected to a pipe 59 by a fitting 13 (Figure 2); pipe 59 is in turn connected to a fitting 88. Fitting 88 is connected to a fitting 8| and fitting 8| is connected to a fitting 82 (Figure 1) by a pipe 83. Fitting 82 is also connected to the intake side 22a of pump 22. The outlet side 22b (Figure 2) of pump 22 is connected to a pipe 84 leading to cooling coils diagrammatically indicated at 19 (Figure 3). A pipe 85 (Figure 3) leading from cooling coils 19, is connected to a fitting 88, and, as diagrammatically indicated in Figure 1, fitting 88 is connected to spray head 89 in evaporator 33 by a pipe 81.

As diagrammatically indicated in Figure 1, Venturi-purge 38 is connected to apparatus diagrammatically indicated at 88 by a pipe 89. Apparatus 88 is connected to the bottom of condenser coils 18 (Figure 1) by a pipe 18 and is also connected to a pipe 51 leading from the bottom of evaporator 33 by a pipe 1|, diagrammatically indicated in Figure 1.

Referring now to Figures 1 and 2, a thermostatic valve 12 is connected to fitting 13 by a pipe 14; the outlet side of valve 12 is connected to a drain element 15 by a pipe 18a. From a consideration of Figure 2, it will be seen that thermostatic valve 12 is connected to fitting 13 substantially along the horizontal center line of pump 22. Accordingly, upon the opening of valve 12, pump 22 and its connected parts including cooling coils 19, evaporator 33 and apparatus 88 will be drained; pump 22, however, will only be drained to the level of pipe 14 (Figures 1 and 2). Valve 12 like valve 55 is constructed to open and remain open at or below any predetermined temperature and 40 F. has been found to be a practical operating temperature for this valve.

Accordingly it will be seen that upon the opening of valves 55 and 12, the majority of the apparatus is drained with the major exception of the make-up tank 88 which is closed oil from the drainage system by valve 44. In fact, the only water remaining in the system after the drainage of the apparatus through valves 55 and 12 is that below the connection of pipe 54 and sump tank 2| and below the connection of pipe 14 with pump 22 along the horizontal center line thereof as described above. As noted above, these connections are preferably positioned along the horizontal center lines of the respective pumps 28 and 22. Consequently, a small amount of water remains in each pump suflicient to keep the pumps in good condition and adequately primed for immediate operation upon a later starting of the system. The small amount of water remaining in sump tank 2|, pump 28, and pump 22 is insufiicient to do any damage in very low temperatures. However, when the system is first started, suflicient water for the operation thereof is soon returned to the system. This is accomplished first by the opening of valve 44 to replenish the condenser cooling system from make-up tank 99 through sump tank 2!; and second, by the operation of condenser 16 to create an excess of condensate therein which enters the system when needed by way of apparatus 69 and connected parts.

A convenient electrical control system for the apparatus described above is shown in Figure 4 wherein a dual source of electricity at the same voltage is employed with two positive lines 99 and 9i and a common negative line 92. Air fans are generally provided for circulating air past the cooling coils 19 (Figure 3) and the condenser coils 16 (Figure 1) and in the circuit to be described motor 93 drives the air fan for cooling coils i9 and motor 94 drives the air fan for condenser coils 16.

Positive line 99 is connected to one side of a solenoid 95 forming a part of a solenoid switch generally indicated at 99. Line 99 is also connected to one side of motor 93 and the other side of motor 93 is connected by a conductor 98 to a contact 4 on a switch generally indicated at 91. Contact l of switch 91 is connected to a conductor 99 which is in turn connected to negative line 92. Consequently, upon the closing of switch 9i to bridge contacts I and 4 thereof, a circuit is established from line 92 through air fan motor 93 to line 99.

A thermostatic switch I99 is located in the space to be cooled such as the interior of a railroad car and constructed to close whenever the temperature of the enclosure rises above that desired. One side II9I of switch [I99 is connected to a conductor I92 which in turn connects with a conductor I93 the left end of which is connected to solenoid 95 of a switch 96. Switch I99 is connected at the other side I94 to a conductor I99 which'is connected through a conductor I96 to a contact 5 of switch 91. When switch 91 is closed, contact 5 is connected to contact I, and, thus, a direct connection is provided from negative line 92 through conductor 99 and switch 91 to conductors I99 and E95. With switch 91 closed when the car thermostat switch I99 closes, this direct connection from negative line 92 is extended along conductors I92 and I93 to the negative side of solenoid 95. The other side of solenoid 95 is connected to positive line 99. Thus, when switch 9? and car thermostat switch I99 are closed, the full voltage between lines 99 and 92 is impressed directly across solenoid 95. Switch 99 is provided with a contact it? and a contact I99, and when solenoid 99 is energized, switch arm I32 is moved across these contacts to close the switch.

Positive line M is connected to contact I91 of switch 96 by a conductor I99; contact I99 of switch 99 is connected to one side of motor I9, one side of make-up water valve 44 and one side of condenser fan 94 by a conductor H9 and respective conductors III, H2 and H3 con-. nected thereto. The otherside of condenser pump motor I 9, make-up water valve 44 and condenser ian 99 are connected to negative line 92 by conductors H4, H5 and H6.

Conveniently, the apparatus described above contains a pressure switch II1 (Figure 4) and a motor valve 84 (Figure 1) in the steam line 83. Switch M1 is constructed to open when the pressure in the steam line is below that desired for the operation of the apparatus and motor valve 94 is constructed to open when energized. Furthermore, a pressure switch H9 responsive to the pressure in the condenser coils 16 is also pro-.-

vided; switch H8 is constructed to close only when the pressure within the condenser coils 19 is low enough for the reception of steam from ejector 34. Motor valve 94 is connected to one side III of steam pressure switch II1 by a conductor I29. The other side MI 01' steam pressure switch H1 is connected to a conductor I29 which connects with a conductor I24; the left hand end of conductor I24 is connected to one side I22 of condenser pressure switch H8. The other side I25 of condenser pressure switch H9 isconnected to positive line 9|. Thus, when switches H8 and H1 are closed, a direct connection is provided between positive line 9I through switch H9, along conductors I24 and I23, through switch H1, and along conductor I29 to one side of motor valve 84. The other side of motor valve 84 is connected to conductor I93 which, as pointed out above, is connected to negative line 92 when switches I99 and 91 are closed. Accordingly, with switches H9, 1, I99, and 91 closed, afull voltage between lines 9| and 92 is impressed directly across motor valve 94.

Conductor I24 is connected at its right end to one side of a solenoid I29 forming a part of a solenoid switch generally indicated at I21. The other side of solenoid I26 is connected to conductor I96 which, as pointed out above, is connected to contact 5 of switch 91, and when switch 91 is closed, a direct connection is provided from negative conductor 92 through switch 91, along conductor I96 to one. side of solenoid I29. With switch II8 also closed and the other side of solenoid I26 thus directly connected to negative line 9I, the full voltage between lines 9I and 92 is impressed directly across solenoid I26. Switch I21 is provided with two contacts I28 and I29 and with an arm I33; when solenoid I26 is energized, arm I33 is moved across contacts I29 and I29, and. the switch is, thus, closed. Contact I29 of switch I21 is connectedto negative line 92 and-the other contact I29 is connected to one side of the cold water pump motor 23 by a conductor I39. The other side of cold water pump motor. 23 is connected to positive line 9| by a conductor I3I and when switch I21 is closed, the full voltage between lines 9I and 92 is impressed directly across cold water pump motor 23. Y

Upon the closing of switch 91 to bridge contacts I and 5 and I and 4 thereof, the system is in condition for operation and such operation is dependent upon the closing of thermostatic switch I99., As pointed out above, the closing of switch 91 completes a circuit to air fan 93 which continues to operate regardless of the operation of the cooling apparatus per se.

When thermostatic switch I99 closes, a circuit is completed through solenoid 95 of switch 96 comprising positive line 99 to one side of solenoid 95 and the left hand end of conductor I93, conductor I92, conductor I95, contacts 5 and I of switch 91 and conductor 99 to negative line 92. The energization of solenoid 95 closes switch 96 to bridge contacts I91 and I99 thereof thereby completing circuits to condenser pump motor I9, make-up water valve 44 and condenser fan 94. The condenser pump motor I9 circuit comprises conductor II4 to negative line 92 and conductors III, II9, contact I99, arm I32, contact I91 and conductor I99 to positive line 9|. The make-up water valve circuit comprises conductor II5 to negative line 92 and conductors H2 and 9, contacts I99 and I91, arm I32 and conductor I98 to positive line 9|. The condenser fan motor circuit comprises conductor II6 to negative line 92 and conductors III and Ill, contacts I09 and III,

arm I32 and conductor I to positive line 9i.

Accordingly, with switch 91 closed, the closing of thermostatic switch I00 causes the condenser pump I9 to start and condenser fan 90 starts to reduce the pressure in the condenser coils as described above. The closing of switch III also energizes make-up water valve 44 to open this valve and thus supply the condenser cooling system with water when needed. The operation of these parts continues until the pressure in the condenser coils I6 is sufflciently low to close switch I".

Assuming that switch I I0 is closed and that the pressure in the steam line is suflicient to close switch I", the circuit explained in detail above is completed to motor valve 04 to open the valve and allow steam to pass therethrough to ejector 3|. This circuit to one side of motor valve 04 comprises conductor I03 connected to one side of the motor valve, conductor I02, switch I00, conductor I05, conductor I06, contacts 5 and I of switch 91, conductor 99 to negative line 92; and from the other side of motor valve 04 comprises conductor I20, switch III, conductor I23, conductor I24, switch H0 to positive line 9i.

The closing of condenser pressure switch H0 also completes a circuit to solenoid I26. This circuit comprises positive line 9|, switch H9, and conductor I24 to one side of the solenoid; and conductor I06, contacts 5 and I of switch 91, conductor 99 from the other side of the solenoid to negative line 92.

Energization of solenoid I26 closes switch I21 to bridge contacts I29 and I29 thereby completing a circuit to cold water pump motor 23. This circuit comprises conductor I3I to positive line 9| and conductor I30, contact I 29, arm I33, contact I20 to negative line 92. All circuits are thus completed and the system is in full operation.

When the temperature of the space being cooled is brought down to that preferred, thermostatic switch I00 opens to break the circuit of solenoid 95 thus opening switch 96 and breaking the circuit of condenser pump motor l9, make-up water valve 44 and condenser fan 94. The opening of thermostatic switch I00 also breaks the circuit of motor valve 94 thus to cut off the supply of steam to the system. In this embodiment, the system is held vacuum tight, when not operating, through the action of apparatus 60 with the result that switch IIB remains closed, and cold water pump motor 23 continues to operate the pump until the connection between contacts I and 5 of switch 91 is broken. Air fan motor 93 also continues to operate until the connection is broken between contacts I and I of switch 91. The remainder of the system remains inoperative until thermostat switch I09 is again closed.

It should be particularly noted that the operation of cold, water pump motor 23 and consequently the circulation of water in the cooling coils I6 is directly under control of condenser pressure switch H9. Consequently cold water will not be circulated through the coils and through the evaporator unless the pressure in the cor jenser coils is sufllciently low for .the operation of the condenser. This is particularly important because the cold water system including the coils I6 and the evaporator 33 are dependent for replenishment of water from steam condensate in the condenser coils as described above.

If such parts should operate when the condenser was not operating, damage thereof might occur. Furthermore, it should be noted that the make-up water valve 44 controlling the flow of water from make-up tank 00 (Figure 2) to sump tank 2 I is in the same circuit as condenser pump motor I9. Consequently, valve 44 is always closed when the condenser pump is not operating. As noted above, the opening of valve 66 (Figure 2) might drain the make-up tank 00 if valve 44 was open. However, valve 44 is always closed when condenser pump I9 is inoperative and the apparatus never operates at a temperature sufficiently low to open valve 55.

It will thus be seen that I have provided a practical and eflicient system and apparatus for accomplishing the several objects hereinabove mentioned as well as many others in a successful manner.

As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth, or shown in the accompanying drawings, is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In refrigerating apparatus, in combination, a frame, a pump suspended from said frame, a cooling coil suspended above said frame, an evaporator suspended above said pump, pipes connecting said pump, said coil and said evaporator, and a drain connected to said pump to drain water from said pump, said evaporator and said coll when the atmospheric temperature falls to a predetermined level.

2. In refrigerating apparatus, in combination, a frame, a rotary pump suspended from said frame, a cooling coil mounted above said frame, an evaporator mounted on said frame above said pump, ipes connecting said pump, said coil and said evaporator, and a thermostatically controlled drain connected to said pump at a point substantially intermediate the top and bottom thereof.

3. In refrigerating apparatus, in combination, a frame, a sump suspended from said frame, a pump suspended from said frame, a motor for driving said pump, a condenser located above said pump and sump, a water cooling device associated with said condenser and connected to said pump, said cooling device, said sump and said pump being interconnectui, a make-up tank located above said pump and said sump, a pipe connecting said make-up tank to said sump, and

an electrical valve in said pipe constructed to open when energized and in the circuit of said motor.

4. In refrigerating apparatus, in combination, a frame, a sump suspended from said frame, a pump suspended from said frame, a motor for driving said pump, a condenser located above said pump and sump, a spray device for said condenser connected to said pump, said cooling device, said sump and said pump being interconnected, a make-up tank located above said pump and said sump, a pipe connecting said make-up tank to said sump, an electrical valve in said pipe constructed to open when energized and in the circuit of said motor, and a thermostatically controlled drain connected to said pipe.

5. In air conditioning apparatus for a railroad car or the like, in combination, an evaporator and a condenser suspended beneath the car, a steam ejector connected to said evaporator and suspended beneath said car, a sump and pump suspended beneath said car below said condenser, a water cooling device associated with said con- .denser, pipes connecting said sump, pump and spray device, a pump suspended beneath said car, cooling coils disposed within said car, pipes connecting said last-mentioned pump, said cooling coils and said evaporator, and thermostatically controlled valves arranged to drain said last-mentioned pump and said sump.

6. In air conditioning apparatus for a railroad car or the like, in combination, an evaporator and a condenser suspended beneath the car, a steam ejector connected to said evaporator and suspended beneath said car, a sump and pump suspended beneath said car below said condenser,

a spray device for directing water over said condenser, pipes connecting said sump, pump and spray device, a pump suspended beneath said car, cooling coils disposed within said car, pipes con necting said last-mentioned pump, said cooling coils and said evaporator, a make-up water tank disposed within said car above said sump and connected thereto, and a valve for controlling the fiow of water from said make-up tank to said sump, said valve being interrelated with said firstmcntioned pump to be opened during the operation of said first-mentioned pump.

7. In air conditioning apparatus for a railroad car or the like, in combination, an evaporator and a condenser suspended beneath the car, a steam ejector connected to said evaporator and suspended beneath said car, a sump and pump suspended beneath said car below said condenser, a spray device for directing water over said condenser, pipes connecting said sump, pump and spray device, a pump suspended beneath said car, cooling coils disposed within said car, pipes connecting said last-mentioned pump, said cooling coils and said evaporator, a make-up water tank disposed within said car above said sump and connected thereto, a valve for controlling the flow of water from said make-up tank to said sump, said valve being interrelated with said first-mentioned pump to be opened during the operation of said first-mentioned pump, and thermostatically controlled valves arranged to drain said sump and said last-mentioned pump.

8. In refrigeration apparatus including a cold water cooling system, the combinatiomof a cooling coil in said system, a pump for circulating cold water through said coil, a condenser in said system, and means responsive to the pressure in said condenser for controlling the operation of said pump.

9. In refrigerating apparatus, in combination, a frame, an evaporator supported on said frame, a cooling coil mounted above said frame, a pump suspended on said frame beneath said evaporator, pipes connecting said evaporator, said pump and said coil, and a thermostatic valve connected to said pump above the bottom thereof.

10. In a cooling system, in combination, refrigerating apparatus dependent upon evaporation of water to effect refrigeration, a pump connected to said apparatus and located therebelow, and a thermostatic valve connected to said pump above the bottom thereof and set to open at a tempera.- ture somewhat above freezing to empty said apparatus and partially empty said pump.

11. In air conditioning apparatus for a railroad car including a cold water cooling system and a. tank for replenishing the water in said system, the combination of a cooling coil in said system, an evaporator in said system, a pump,

an electric motor for driving said pump for circulating water between said coil and said evaporator in said system, and an electrical valve constructed to open when energized and in the circuit of said motor, said valve being disposed between said system and said tank for controlling the flow of water from said tank to said system.

12. In refrigeration apparatus, in combination, a cooling coil, means for circulating a cooling medium through said coil, an electric motor for operating said last-mentioned means, a condenser, and a switch in the circuit of said motor and responsive to the pressure in said condenser, said switch adapted to close only when pressure in said condenser is reduced to v a predetermined level.

13. The combination of refrigerating apparatus mounted upon a railroad car including a number of interconnected parts, said apparatus being dependent upon water to effect the refrigerating operation, valve means connected to the lower portion of said apparatus for drainage of said apparatus, and thermostatic means operably connected to said valve means and set to effect the opening of said valve means at a temperature somewhat above the freezing point of water and to maintain the valve closed at any temperature above said temperature.

14. The combination of refrigerating apparatus including a number of interconnected parts, said apparatus being dependent upon evaporation of water to effect refrigeration, valve means connected to the lower portion of said apparatus for drainage of said apparatus, and thermostatic means operably connected to said valve means and set to effect the opening of said valve means at a temperature somewhat above the freezing point of water and to maintain the valve closed at any temperature above said temperature.

15. In a cooling system, in combination, an evaporator, a condenser, liquid cooling apparatus for said condenser, and thermostatic drainage equipment connected to said evaporator, condenser and cooling apparatus and set to open at a temperature somewhat above the freezing point of the liquid in said cooling apparatus.

16. In a cooling system, in combination, a condenser, water cooling apparatus for said condenser, water circulating means located below said apparatus and connected therewith including an interconnected pump and sump, and a thermostatically controlled drainage device connected to said means.

17. In a cooling system, in combination, a frame, apparatus suspended on said frame at approximately the same level including a sump and a pump connected to said sump, a drain connected to said apparatus above the bottom thereof, and a thermostatic valve connected to said drain and set to open at atemperature somewhat above freezing.

. 18. In refrigerating apparatus, in combination, a frame, a tank supported on said frame, a condenser located within said tank, a spray device located within said tank and arranged to spray water on said condenser, a sump connected to the bottom of said tank and suspended beneath said frame, a pump connected to said sump and said spray device to draw water from said sump to said spray device, said pump being suspended beneath said frame, and a thermostatically controlled valve connected to said sump above the bottom thereof.

19. In refrigeration apparatus including a cold water cooling system, the combination of, a frame,

an evaporator supported on said frame, a steam ejector device connected to said evaporator and supported on said frame, a condenser connected to said steam ejector device, means for directing steam through said steam ejector device, a container for said condenser supported on said frame, a spray device for said condenser mounted in said container, a rotary pump suspended from said frame and connected to said spray device, a sump suspended from said frame, pipes interconnectin said sump, said pump, said spray device and said container, a cooling coil mounted above said 

